Fuse plug



D562. 3, 1929. H. F. DELMANHORST 4 FUSE PLUG Filed July 16, 1925 F\G.8 INVENT R g e Z t 9 I I Q) 1 TTORNEY Patented Dec. 3,1929

them in order to UNITED STATES PATENT; OFFICE HERMAN? F. DELMANHOBST, OF LOUISVILLE, KENTUCKY, ASSIGNOR, BY KESNE AS- SIGNMENTS, TO NILES MACHINE COMPANY, OF LEBANON, NEW HAMPSHIRE FUSE PLUG Application filed July 16,

y particularly on comparatively low voltage and small amperage, such as are generally used for lighting circu ts and for small power units,

In fus plugs of this type in general use,

and consequently when a fuse has blown, it is usually necessary to remove several and to examine find out which one must be renewed and a new fuse must necessarily be used to renew the blown one.

The object and purpose of my invention is to provide a fuse plug hich vwhen blown will. be readily distinguishable from the'live or ood ones.

nother object and purpose of my inven tion is toprovide-a fuse plug which willbe' readily renewable by replacing the burned fuse element, and that fuse element shall be of such form as to make it readily and easily installed at a minimum price, making a cheap, highly efiicient, simple and safe fuse plug, possessing marked utility. In the accompanying drawing, forming part of this specification:

Fig. 1, is a side view of a fuse plug embodying my invention, Fig. 2, is .a bottom view of the fuse plug shown in Fig. 1,

Fig. 3, is a bottom view of the fuse plug 1 shown in Fi 1, as it would appear if the fuse has blown Fig. 4, is a section on line 4-4 of Fig. 2,-

Fig. 5, is a section on line 5- 5 of Fig. 3, Fig. 6, is a bottom view of. fuse plug as shown in Fig. 4, with the. cap removed,

Fig. 7, is a bottom view of fuse plug shown in Fig. 5, with cap removed, and I Fig. 8, is an isometric view of the fuse ele ment to be used with my fuse plugl This fuse plug consists of a-body 1, made of an insulating material, composed of a cymount a metal ferrule 3, in any suitable manner, the said metal ferrule 3 adapted to enage the threaded part of a socket; the said errule also carries a tongue .or hook 4 adapt ed to hold one end of thefuse 8; the said invention relates to fuse plugs, more or target 9, and a notch or blows, the spring 1925. Serial No. 43,913.

tongue or hook extending through a slot 5 in the body 1.

I also provide a rivet 6, or its equiyalent, to form one of the contacts with the socket.

A spring hook 7 isheld in place by the rivet 6, and carries at its outer end the indicator the fuse link 8. v A cap 11, made of any suitable material, is provided with ahole12, and is secured to the body portion 1, the lugs 13 on the said body portion being engaged by the oblique slots 14 of the cap 11.

A. layer of mica 15 the body I and is held in place by the cap 11,-thus preventing flashing when the fuse burns out. p

The operation of this fuse plug is very simple, the fuse link 8 being placed over the hook 7, the target 9 being drawn toward the hook ,4 until the fuse link engages saidhook 4, thus forming a fusible connection between the rivet 6 and the sleeve or ferrule 3 and at the same time holding the target in a position where it cannot be seen through the hole 12 in the cap 11, but when this fuse burns out 7 is released allowing the target to take the position shown in Fig. 7, making itv visible t rough the hole 12 in the cap 11 as shown in Fig. 3.

The tongue 4 and the spring hook7 may be termed leads, which, in connection with the rivet or contact point 6 are capable of connection with an electrical circuit. It will readily become apparent that I provide a renewable fuse automatic self-indicating fuse plug. The target may be colored to make it quickly and plainly visible, and it may be connected up in any manner other than herein set forth. I

My invention may be applied to an fuse plug of a varying construction than erein set forth which is capable of receiving the same. The .fuse link may be made of any material' found practicable for the purpose.

- What I cla1m as new and my'invention and desire to secure by Letters Patent is 1. A fuse plu' comprisin a cup-s'aped 10, adapted to hold I covers the opening in 9 is anindicating device, and

. arranged on ti cover closing the mouth of the cup-shaped body and provided with a sight opening, first and second electric conducting elements extending into said body, the first conducting element being adapted to spring away from the second one of said elements, and a removable fusible link loosely connected to said elements, and adapted to hold the first element under tension, one of said electric elements having an indicator normally held out of alignment with the sight opening by said fusible link, he indicator being adapted when the link is severed, to move into alignment with the lit opening.

2. An electrn Eusc plug comprising a cupshaped body of insulating material, a removable cover closing the mouth of said body, a threaded fe -dc, of conducting material periphery of said body and secured to the latter, said body having an opening in its side Wall, a tongue connected to the ferrule and extending through said opening into the interior of the body, a conducting element connected to the bottom of the body, a resilient tongue arranged in the body and electrically connected to the last mentioned element, a detachable fusible link connecting said tongues, said cover having a sight opening, and said resilient tongue having-a target normally arranged out of alignment with the sight opening, and adapted when the fusible link breaks alignment with the sight opening, and indicate that the fuse has been blown; said link being adapted to be threaded about the ends of said tongues.

In testimony whereof, I aihx my signature at Louisville, Kentucky, this 3rd day of July,

HERMAN DELMANHQRST.

to move into 

